The period from the start of resumption of spring vegetation of winter cereals to stem elongation is quite critical and has a substantial influence on the yield of these crops. Every year part of the winter cereal area is in unsatisfactory condition, and some of it even has to be resown because of significant thinning. The main reason for this phenomenon is late sowing after worse preceding crops, when, because of moisture deficit, seedlings appeared later than the optimal dates and therefore entered winter weakened, with a poorly developed root system. Factors that adversely affect the state of crops during overwintering include frequent thaws, which fortunately were not observed in the first half of winter 2016/2017, but it is unknown what weather conditions will develop during February–March and how this will affect winter cereal plants.
The cold, prolonged spring forecasters predict will also not help the state of problem crops. Unfavorable weather conditions, insufficiently warmed soil and its dried-out upper part, especially on thinned, poorly developed crops, do not let the plant provide the necessary level of mineral nutrition, and hence the formation of a high-yielding biocenosis.
Traditional nitrogen feedings are not enough in such conditions. It is important that plants are sufficiently supplied with other important nutrients, in particular phosphorus and potassium. If supplying plants with available potassium may present no difficulties, at least in theory, since potassium is more mobile in the soil, the situation with phosphorus looks much more complicated. Phosphorus is of decisive importance for accelerating the growth and development of the root system, the plants' main organ that supplies them with nutrients and water. However, because of the meagre uptake of this element from cold soil, feeding with traditional phosphorus-containing fertilizers is practically impossible, owing to the specifics of its mobility and therefore its availability to plants. Low soil temperature (<13 °C) leads to phosphorus shortage for plants even when its content in the soil is high. In these conditions the viscosity of the soil solution rises and phosphorus supply by diffusion falls. Observant agronomists often notice visual signs of phosphorus shortage, which already points to a significant deficiency of this mineral nutrient. The importance of phosphorus for plants in the early spring period is many-sided. First of all, its influence on root system growth and development is extremely significant. No less important is its influence on metabolism in the plant, in particular the synthesis of simple organic substances, first of all sugars and proteins. An insufficient level of mineral nutrition significantly reduces the protective functions of plants and they become extremely vulnerable to disease, first of all of fungal nature. All this can lead to significant losses in both the volume and quality of the yield.
The question arises: «Is there a way to help the plant with phosphorus and potassium supply and at the same time strengthen plant immunity to disease agents?»
To support plants with a poorly developed root system in a period of minimal mineral nutrient uptake (low air temperature, cold soil), the most effective measure is foliar feeding with special fertilizers.
In this case Ecoorganic recommends using, for foliar feeding, special fertilizers with phosphorus in the form of phosphite, which improve phosphorus nutrition and promote the synthesis of special phytoalexin proteins, the natural guardians of plant immunity.
What is the advantage of the phosphite form of phosphorus?

  1. Plant uptake of phosphorus as phosphite PO3 is more intensive than of phosphates PO4. When applied to the leaf, phosphorus in phosphite form is absorbed to the extent of 65–75% of the applied amount in just 24 hours. Uptake of phosphorus in phosphate form takes no less than 5 days, and even over this long period the uptake level will be no more than 20% of the amount applied.
  2. The action of phosphites as fungicides and biostimulants is built on inducing plant resistance to biotic stress factors (which cause disease) and abiotic ones (for example, low or high temperature), through the synthesis of phytoalexins, which are the guarantee of active immunity. Phytoalexins are a group of organic substances of protein nature produced by the plant in response to pathogen waste products entering the cell or to stress. These compounds are a component of the plant's natural immune mechanism.
  3. It has been proved that phosphites in the root system directly inhibit the development of fungi that cause a number of plant diseases and also stimulate the plant's own protective mechanisms. On cereal crops these are snow mold, powdery mildew and various kinds of rust. Phosphites have an insignificant effect on the development of most soil fungi, which makes their use ecological and safe for the environment. The stability of phosphites in plants is a key factor in their effectiveness in controlling disease agents over quite a long period of time.
  4. With foliar application phosphites have a deeper effect than only a fungicidal one. Phosphorus from phosphite stimulates metabolic processes in plants, which shows in stronger root system growth, uptake of other mineral nutrients, and synthesis of phosphorus-containing biologically active substances, fatty acids, ATP and nucleic acids, raising yield and harvest quality.

Ecoorganic offers its own special fertilizers for foliar feeding of winter crops in this period:

  1. The special concentrated fertilizer Ecoline Phosphite K, which in content of phosphorus in phosphite form and potassium has no analogues in the world.
    The product contains:
    530 g/l of phosphorus as phosphite;
    350 g/l of potassium;
    14 g/l of boron.

    Recommended application rate in this period is 1.0–1.5 l/ha.
    The fertilizer can be applied with urea solutions, UAN or crop protection products.
  2. In cases when the influence of stress factors (chemical or weather) on the plant is observed in this period, it will be advisable to use the special fertilizer Ecoline Phosphite K-Amino, which contains 250 g/l of phosphorus as phosphite, 170 g/l of potassium, and also 70 g/l L-α-amino acids, which help the plant overcome stress successfully.
  3. If, according to leaf diagnostics results, zinc shortage in plants is found, the fertilizer Ecoline Phosphite K-Zn, which contains 320 g/l of phosphorus as phosphite, 210 g/l of potassium and 35 g/l of zinc as EDTA chelate will help effectively correct this imbalance.